SDGPSLogger

The SD GPS logger will take data from a GPS and log it into a file on an SD card every 5 seconds.

It is based on the Arduino with an SD card shield and an attached GPS.

Here is the source code for the arduino:

/*
SD gps datalogger
This will log locations to a file on an SD card.
Known bugs:
If the code writes to the SD card at the same time you power down, it
can corrupt the file system on the SD card.
Pins:
SD MOSI - pin 11
SD CLK - pin 13
SD CS - pin 8
GPS serial out - pin 7
GPS serial in - pin 6 (not needed)
SD Shield:
http://www.sparkfun.com/products/9802
GPS:
http://www.byonics.com/tinytrak/gps.php (GPS2)
Required Libraries:
NewSoftSerial - http://arduiniana.org/libraries/newsoftserial/
TinyGPS - http://arduiniana.org/libraries/tinygps/
Copyright (C) 2011 Jay Sissom
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; version 2
of the License. THIS SOFTWARE IS RELEASED UNDER THE TERMS OF
VERSION 2 OF THE GPL LICENSE ONLY.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
http://www.gnu.org/licenses/gpl-2.0.html
Jay Sissom jsissom@gmail.com
*/
#include <SD.h>
#include <NewSoftSerial.h>
#include <TinyGPS.h>
// GPS and serial objects
TinyGPS gps;
NewSoftSerial nss(7,6,true);
// GPS data (global so we don't need to pass them around)
long lat, lon;
int year;
byte month, day, hour, minute, second, hundredths;
unsigned long age, date, time, chars, speed;
bool moving = true;
// On the Ethernet Shield, CS is pin 4. Note that even if it's not
// used as the CS pin, the hardware CS pin (10 on most Arduino boards,
// 53 on the Mega) must be left as an output or the SD library
// functions will not work.
const int chipSelect = 8;
void setup() {
Serial.begin(9600);
Serial.print("Initializing SD card...");
// make sure that the default chip select pin is set to
// output, even if you don't use it:
pinMode(10, OUTPUT);
// see if the card is present and can be initialized:
if (!SD.begin(chipSelect)) {
Serial.println("Card failed, or not present");
// don't do anything more:
return;
}
Serial.println("card initialized.");
nss.begin(4800);
Serial.println("GPS initialized.");
}
void loop() {
bool newdata = false;
unsigned long start = millis();
// Every 5 seconds we write an update (if we are moving)
while (millis() - start < 5000) {
if ( feedgps() ) {
newdata = true;
}
}
if (newdata) {
speed = gps.speed();
gps.get_position(&lat, &lon, &age);
feedgps();
gps.get_datetime(&date, &time, &age);
feedgps();
gps.crack_datetime(&year, &month, &day, &hour, &minute, &second, &hundredths, &age);
feedgps();
// Only write data if we are moving
if ( moving ) {
writeData();
}
moving = ( speed > 85 );
} else {
Serial.println("No GPS data during the last 5 seconds");
}
}
bool feedgps() {
while (nss.available()) {
if (gps.encode(nss.read()))
return true;
}
return false;
}
void writeData() {
// open the file. note that only one file can be open at a time,
// so you have to close this one before opening another.
File dataFile = SD.open("datalog.txt", FILE_WRITE);
// if the file is available, write to it:
if (dataFile) {
feedgps();
dataFile.print(lat);
dataFile.print("\t");
dataFile.print(lon);
dataFile.print("\t");
dataFile.print(gps.altitude());
dataFile.print("\t");
feedgps();
dataFile.print(year);
dataFile.print("\t");
dataFile.print(static_cast<int>(month));
dataFile.print("\t");
dataFile.print(static_cast<int>(day));
dataFile.print("\t");
dataFile.print(static_cast<int>(hour));
feedgps();
dataFile.print("\t");
dataFile.print(static_cast<int>(minute));
dataFile.print("\t");
dataFile.print(static_cast<int>(second));
dataFile.print("\t");
dataFile.print(gps.course());
dataFile.print("\t");
dataFile.print(speed);
dataFile.print("\t");
dataFile.println(age);
feedgps();
dataFile.close();
} else {
Serial.println("error opening datalog.txt");
}
// print to the serial port too:
feedgps();
Serial.print(lat);
Serial.print("\t");
Serial.print(lon);
Serial.print("\t");
Serial.print(gps.altitude());
Serial.print("\t");
feedgps();
Serial.print(year);
Serial.print("\t");
Serial.print(static_cast<int>(month));
Serial.print("\t");
Serial.print(static_cast<int>(day));
Serial.print("\t");
Serial.print(static_cast<int>(hour));
feedgps();
Serial.print("\t");
Serial.print(static_cast<int>(minute));
Serial.print("\t");
Serial.print(static_cast<int>(second));
Serial.print("\t");
Serial.print(gps.course());
Serial.print("\t");
Serial.print(gps.speed());
Serial.print("\t");
Serial.println(age);
feedgps();
}

Here is the source code for a perl program that will read the data file on the SD card and generate a kml file that can be read by google earth:

Use it like this:

perl converter.pl < sd_data_file.txt > output.kml

#!/bin/perl
# Copyright (C) 2011 Jay Sissom
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; version 2
# of the License. THIS SOFTWARE IS RELEASED UNDER THE TERMS OF
# VERSION 2 OF THE GPL LICENSE ONLY.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
#
# http://www.gnu.org/licenses/gpl-2.0.html
#
# Jay Sissom jsissom@gmail.com
print "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n";
print "<kml xmlns=\"http://earth.google.com/kml/2.0\">\n";
print " <Document>\n";
print " <Placemark>\n";
print " <LineString>\n";
print " <coordinates>\n";
while ($line = <STDIN>) {
@data = split(/\t/,$line);
$latitude = $data[1]/100000;
$longitude = $data[0]/100000;
print " $latitude,$longitude,0\n";
}
print " </coordinates>\n";
print " </LineString>\n";
print " <Style>\n";
print " <LineStyle>\n";
print " <color>#ff0000ff</color>\n";
print " <width>5</width>\n";
print " </LineStyle>\n";
print " </Style>\n";
print " </Placemark>\n";
print " </Document>\n";
print "</kml>\n";

Here is the source code for a ruby program to convert the text file to a kml file. Put this into a file named tokml.rb and run it like this:

ruby tokml.rb input_file_name output_file_name

# Copyright (C) 2011 Jay Sissom
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; version 2
# of the License. THIS SOFTWARE IS RELEASED UNDER THE TERMS OF
# VERSION 2 OF THE GPL LICENSE ONLY.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
#
# http://www.gnu.org/licenses/gpl-2.0.html
#
# Jay Sissom jsissom@gmail.com
class ToKml
def generate_kml(input_file_name,output_file_name)
File.open(output_file_name,'w') do |out|
out.puts "<?xml version=\"1.0\" encoding=\"UTF-8\"?>"
out.puts "<kml xmlns=\"http://earth.google.com/kml/2.0\">"
out.puts " <Document>"
out.puts " <Placemark>"
out.puts " <LineString>"
out.puts " <coordinates>"
File.open(input_file_name,'r') do |fl|
while line = fl.gets
data = line.split("\t")
latitude = data[1].to_f / 100000.0
longitude = data[0].to_f / 100000.0
out.puts " #{latitude},#{longitude},0"
end
end
out.puts " </coordinates>";
out.puts " </LineString>";
out.puts " <Style>";
out.puts " <LineStyle>";
out.puts " <color>#ff0000ff</color>";
out.puts " <width>5</width>";
out.puts " </LineStyle>";
out.puts " </Style>";
out.puts " </Placemark>";
out.puts " </Document>";
out.puts "</kml>";
end
end
end
if __FILE__ == $0
if ARGV.length != 2
puts "Must pass the source file name and target file name on the command line"
exit(1)
end
tk = ToKml.new
tk.generate_kml(ARGV[0],ARGV[1])
end